The present invention relates to an apparatus for producing motion-simulating movement of a platform. It also relates to an apparatus for producing a signal from movement of a controller.
Many amusement devices simulate motion by providing a platform which moves multi-directionally while a user is seated on the platform. Movement of the platform may be along six degrees of freedom: translational movement along x, y and z axes and rotational movement about the x, y and z axes.
Typically, a platform will be mounted on hydraulic cylinders which tilt the platform. In that case, the platform may be tilted by rotating around the x and y axes and may also be lifted or lowered ie/translational movement along the z axis. In this case, the platform will only have three degrees of freedom of movement. Motion simulators which employ hydraulic cylinders may not be fast acting or may cause abrupt non-natural motions which are not realistic.
In another field of application, controllers for video games or remote control devices translate physical action into electrical signals which are then used to input into the game to create animated motion in the game or to control movement of a device. Typically, the controller is a joystick which may only be moved in two degrees of freedom and therefore which responds to movement which controls movement along the x and y axes. If three-dimensional control is required, the controller must have a second joystick or other secondary controllers.
There is a need in the art for a motion linkage which may allow for translation of motion in at least three degrees of freedom and preferably all six degrees of freedom, either in creating motion in the case of a motion simulator or by translating motion in the case of a controller such as a joystick.
The present invention is directed to a motion translating apparatus which may be used in a motion simulator or in a motion controlling device.
Accordingly, in one aspect of the invention, the invention comprises a motion linkage apparatus having an x axis, a y axis and a z axis, each of which axes is perpendicular to each other, said apparatus comprising:
(a) a base having a central leg substantially in the xe2x80x9czxe2x80x9d axis;
(b) at least three shaft and ball assemblies associated with each leg, each assembly comprising:
i. a ball having a spherical outer surface and a centreline parallel to the xe2x80x9cx-yxe2x80x9d plane; and
ii. a rotating shaft fixed to the ball parallel to but offset from the centreline of the ball;
wherein the axes of the shafts converge on a centre point and radiate outward from the leg and wherein rotation of the shaft displaces the ball eccentrically about the axis of the shaft; and
(c) a platform which has an outer circumference and at least three receptacles, wherein each receptacle engages a corresponding ball such that movement of each ball causes movement of the platform; and
(d) means for independently rotating each shaft associated with the base or legs.
In a preferred embodiment, there are at least three legs located about a periphery of the base instead of a single central leg; at least three shaft and ball assemblies wherein each leg is associated with a shaft and ball assembly, wherein each shaft radiates inwardly and the axes of the at least three shafts converge at a central point; and at least three cylindrical sockets wherein each socket rotatably receives a ball.
In another aspect of the invention, the invention comprises a motion linkage apparatus having an x axis, a y axis and a xe2x80x9czxe2x80x9d axis, each of which axes is perpendicular to the other axes, said apparatus comprising:
(a) a base having a central leg substantially in the xe2x80x9czxe2x80x9d axis;
(b) at least three ball and cam assemblies associated with the leg, each comprising:
i. a ball having a spherical exterior surface, a centreline parallel to the xe2x80x9cx-yxe2x80x9d plane and a cylindrical cavity having a centroidal axis which is parallel to but offset from the centreline of the ball;
ii. a cam which is rotatably mounted within the ball cavity;
iii. an inner shaft attached to the cam in an offset position, for rotating the cam about an axis defined by the inner shaft, wherein said inner shaft axis is coaxial with the centreline of the ball;
iv. an outer shaft which is coaxial with and which may rotate independently of the inner shaft, wherein said outer shaft has a fixed pinion gear and rotates the ball by means of the pinion gear meshing with a circular inner gear attached to the ball;
v. wherein the axes of the inner and outer shafts converge on a centre point and radiate outward; and
vi. wherein rotation of the inner shaft relative to the outer shaft causes the centreline of the ball to be displaced relative to the axis of the inner and outer shafts;
(d) means for counter-rotating each inner shaft and a corresponding outer shaft such that the ball and cam counter-rotate at the same rate; and
(e) a platform having at least three ball sockets wherein each ball rotatably engages a ball socket.
In a preferred embodiment, there are at least three legs located about a periphery of the base instead of a single central leg; at least three ball and cam assemblies wherein each leg is associated with a ball and cam assembly, wherein each shaft radiates inwardly and the axes of the at least three inner and outer shafts converge at a central point; and at least three cylindrical sockets wherein each socket rotatably receives a ball. The inner shafts may pass through each ball and may be supported by a strut which may be a single strut centrally located on the base.
In another embodiment, the apparatus may comprise the combination of two apparatuses as described herein which are joined together at their bases such that one is inverted to the other. In this embodiment, each shaft in one apparatus may be driven by a motor which also drives the equivalent shaft in the other apparatus.
In any embodiment, each inner shaft and each outer shaft may be rotated independently of each other such that platform may be moved in six degrees of freedom
Alternatively, the apparatus may be adapted for use as remote control device or as a joystick-style controller and comprises a sensor or signal feedback device in replacement of the means for rotating the shafts.